This invention relates to a solder-removing apparatus, and more particularly to a solder-removing apparatus suitably used in a repairing operation.
Recently, the added value of electronic parts has increased. When an electronic part has been found defective, it is important not to discard the whole of this electronic part but to use a repair technique in which a defective factor is removed, or only a defective component is exchanged with a new one. In a repairing operation for an electronic part, a soldered part is often removed. In such a case, solder remains on the part, and therefore there is required a technique of leveling the unnecessary solder.
For example, in the case of removing a BGA-type LSI, solder, adhered to the LSI, is heated to be melted, and then a Cu plate is pressed against the LSI. As a result, the solder is transferred to the Cu plate, thus completing the leveling operation. Thereafter, fresh solder balls are supplied to an LSI.
With respect to a high-density module, the whole of the module is formed into a box-shape, and the interior of this module is sealed air-tight so as to prevent moisture and foreign matters from intruding into the module. Solder is used at a sealing portion of the module. In a repairing operation, the sealing portion of the module must be heated to be melted so as to open the module. After the repairing operation is completed, the module is again sealed. At this time, fresh solder is supplied to the sealing portion of the module so that the sealing quality will not be deteriorated. At this time, the residual solder, remaining at the sealing portion, need to be beforehand leveled so that an appropriate amount of solder can be supplied to the sealing portion. In the ordinary leveling technique, however, the leveling is effected in the atmosphere, using a solder wick, a soldering iron and a flux.
However, in the method of leveling the solder by pressing the Cu plate against the solder, there is a possibility that a part (e.g. a bare chip), having an electronic circuit or a protective film formed on a surface of a substrate, is damaged. And besides, in the case where the LSI is large in size, warp of the LSI due to heating increases, so that the Cu plate can not be pressed against the LSI uniformly over an entire area thereof.
Furthermore, in the method of leveling the solder at the sealing portion of the module, using the solder wick and the soldering iron, the efficiency of the operation was low, and besides the leveling quality varied from operator to operator. In addition, since the flux was used, a step of washing the residual flux out was needed.
Namely, with the above methods, the solder could not be properly removed from some members or portions, from which the solder is to be removed, thus inviting a problem that the general-purpose ability was low.
It is therefore an object of this invention to provide a solder-removing apparatus of a high general-purpose ability capable of removing solder regardless of the type of member or portion from which the solder is to be removed.
A solder-removing apparatus of the present invention includes a heating portion for heating the object having the solder adhered thereto, a measuring portion for measuring the distance from the measuring portion to the object, a solder-drawing portion for drawing the molten solder on the object by suction, an X-Y moving portion for moving the object in an X-direction and a Y-direction, a Z moving portion for moving the object relative to the solder-drawing portion in a Z-direction, and a control portion for controlling the X-Y moving portion and the Z moving portion. During the time when the molten solder on the object is drawn by the solder-drawing portion, the control portion causes the X-Y moving portion to move the object, and also causes the Z moving portion to move the object relative to the solder-drawing portion in accordance with the distance, measured by the measuring portion, so that the distance between the solder-drawing portion and the object can be kept constant.
In the solder-removing apparatus, the solder is drawn by the solder-drawing portion while keeping the distance between the solder-drawing portion and the object constant. Therefore, a force is not applied to the object itself. And besides, even when the object has concave and convex portions or the like, the solder can be effectively removed.